$-\dfrac{4}{3} - \dfrac{3}{12} = {?}$
Solution: $ = - {\dfrac{4 \times 4}{3 \times 4}} - {\dfrac{3 \times 1}{12 \times 1}} $ $ = - {\dfrac{16}{12}} - {\dfrac{3}{12}} $ $ = - \dfrac{{16} - {3}}{12} $ $ = -\dfrac{19}{12}$